Study of photovoltaic water pumping system using scalar-DVC based control

Abstract

This paper aims to achieve a control of a photovoltaic water pumping system. The study consists of a photovoltaic generator, an inverter, an induction motor and a centrifugal pump as mechanical load. The model used for global simulation is a closed loop model: the voltage output of PVG model is coupled with the voltage input of the inverter-induction motor model; the current output of this latter is coupled with the current entry of the PVG. The strategy control proposed in this study consist to i) pumping water with Solar energy, ii) drives the machine in constant flux and variable voltage for this subject a closed loop scalar based control law via a direct voltage control (DVC) inverter is used. The MPPT is given by the theory of conservation of energy ensures the control speed. The induction motor model is based on the classic dynamic model in the dq orthogonal Park reference frame. Simulations results confirm the working of the complete model and the effectiveness, feasibility and limits of such approach.